Computer systems are sometimes used to process digital imagery, such as that captured by digital cameras and scanners, into new forms. The processing may include assembling several images into new images, such as mosaics or collages. The present invention includes a method for streamlining the segmentation of a region or volume into smaller regions or volumes. While the examples provided refer to the assembly of collages from multiple source images, the technique is applicable to any task involving the arrangement of multiple two- or three-dimensional regions.